Abstract
The fetal modified myocardial performance index (Mod-MPI) is a noninvasive, pulsed-wave Doppler-derived measure of global myocardial function. This review assesses the progress in technical refinements of its measurement and the potential for automation to be the crucial next step. The Mod-MPI is a ratio of isovolumetric to ejection time cardiac time intervals, and the potential for the left ventricular Mod-MPI as a tool to clinically assess fetal cardiac function is well-established. However, there are wide variations in published reference ranges, as (1) a standardised method of selecting cardiac time intervals used in Mod-MPI calculation has not been established; (2) cardiac time interval measurement currently requires manual, inherently subjective placement of callipers on Doppler ultrasound waveforms; and (3) ultrasound machine settings and ultrasound system type have been found to affect Mod-MPI measurement. Collectively these factors create potential for significant inter- and intraobserver measurement variability. Automated measurement of the Mod-MPI may be the next key development which propels the Mod-MPI into routine clinical use. A novel automated system of Mod-MPI measurement is briefly presented and its implications for the future of the Mod-MPI in fetal cardiology are discussed.
Highlights
Fetal echocardiography has developed over the past 30 years as the primary noninvasive modality used to evaluate fetal cardiac anatomy, haemodynamics, and function [1]
The myocardial performance index (MPI) is a noninvasive pulsed-wave Doppler-derived measure of global myocardial function which has been evaluated in fetal cardiology and is a ratio of isovolumetric to ejection time cardiac time intervals [1]
Lobmaier et al concluded that raised sweep velocities and wall motion filter (WMF) resulted in superior measurement repeatability because of the association of those settings with higher intraclass correlation coefficients (ICCs), optimal machine settings differ between manufacturers
Summary
Fetal echocardiography has developed over the past 30 years as the primary noninvasive modality used to evaluate fetal cardiac anatomy, haemodynamics, and function [1]. The myocardial performance index (MPI) is a noninvasive pulsed-wave Doppler-derived measure of global myocardial function which has been evaluated in fetal cardiology and is a ratio of isovolumetric to ejection time cardiac time intervals [1]. Known as the Tei Index but later termed the MPI, BioMed Research International it is traditionally a pulsed-wave derived index which incorporates measurement of cardiac time intervals and is defined as follows [8]: MPI = (isovolumetric contraction time (ICT). Both atrioventricular and ventricular ejection flows are evaluated to determine constituent time intervals. The fact that it is relatively measurable and can be incorporated into a routine ultrasound examination adds to its utility in the fetal context [18]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
